吐哈探区油气勘探成果及潜力

Achievements and Potential of Petroleum Exploration in Tuha Oil and Gas Province

吐哈探区油气勘探始于20世纪50年代,大规模的油气勘探工作开始于20世纪80年代,相继在吐哈、三塘湖、银额等盆地取得了丰硕的勘探成果,实现了吐哈盆地侏罗系煤系油气、二叠系—三叠系超深稠油和三塘湖盆地古生界火山岩系油气、致密油气等领域的重大突破,落实了吐哈盆地台北凹陷、三塘湖盆地马朗凹陷等富油凹陷,累计提交探明油气地质储量当量8.20×10^8 t,取得了良好的经济效益和社会效益。经过30多年勘探实践,对煤成烃、超深稠油油藏、火山岩油藏、低压油藏、致密油气藏等地质认识不断深化,明确了其油气成藏地质理论、油气藏控藏要素,形成了不同类型油气藏勘探的配套关键技术。吐哈探区各盆地处于低—中勘探程度阶段,剩余勘探潜力大,为保障吐哈油田持续稳产,下一步要精细勘探煤系油气,扩展勘探二叠系和三叠系,加大北部山前带勘探力度;围绕三塘湖盆地,在精细勘探碎屑岩油藏的同时,评价非常规油藏的甜点段和甜点区,着力勘探古生界油气藏;银额盆地的勘探重点仍在天草、查干等凹陷,落实有利勘探区块。

Petroleum exploration in the Tuha oil and gas province started in the 1950s,but large⁃scale oil and gas exploration began in 1980s.Abundant exploration results have been successively achieved in Tuha basin,Santanghu basin,Yin’e basin,etc.,and major break⁃throughs have been made in the exploration for Jurassic coal⁃measure oil and gas,Permian-Triassic ultra⁃deep heavy oil,Paleozoic volca⁃nic oil and gas,and tight oil and gas in Santanghu basin.Some oil⁃rich sags such as the Taibei sag of Tuha basin and the Malang sag of San⁃tanghu basin have been identified with proved oil and gas reserves(equivalent)of 8.20×10^8 tons,indicating good economic and social bene⁃fits.Over more than 30 years of exploration,the geological understandings of coal⁃derived hydrocarbons,ultra⁃deep heavy oil reservoirs,vol⁃canic oil reservoirs,low⁃pressure oil reservoirs,and tight oil and gas reservoirs have been continuously deepened,the geological theory of oil and gas accumulation and the controlling factors of oil and gas reservoirs have been clarified,and key technologies have been formed for different types of oil and gas reservoirs.The study shows that all the basins in the Tuha oil and gas province are in the stage of medium⁃low exploration degree,and the remaining exploration potential is large.To keep stable production,next measures should focus on:1)fine oil and gas exploration in coal⁃measures,expanding exploration to the Permian and Triassic series,and deepening the exploration in the north⁃ern piedmont areas;2)evaluating the sweet spot intervals and zones in unconventional oil reservoirs,and exploring the Paleozoic oil and gas reservoirs while finely exploring clastic oil reservoirs around Santanghu basin;and 3)taking the Tiancao sag,Chagan sag and other sags in Yin’e basin as the key exploration targets,and confirming favorable exploration blocks.